The biggest complaint I get from my private high school students is
about their homework assignments. Generally it's to do a number of
exercises from their textbook. But they tell me that often the
teacher doesn't have time to correct them.

Try to make it a rule. Never give more homework that you can
correct in the next lesson-
I realize the textbooks are full of grammar exercises. To be
truthful I don't like the ones where the student has to fill in the
correct word. Often the students spend hours on these types of
drills and I personally feel that the benefits are not in proportion
to the time dedicated.
It's obviously more work for the teacher, but I recommend that
the teacher,( once she has taught a grammar point), asks the
students to USE it in their own sentences. In this way she
can evaluate if the student really understands the point or not.

This can be a guided activity in the classroom before
she gives this homework assignment. Talking about the future
tense, she can ask the students for examples , using assigned
verbs. Work with the students at the blackboard, for all to see. Let the students suggest sentences. Correct them, but in a way that
they know they are allowed to make a mistake! You're there to help
not holler!!

The verb to visit I will (I'll) visit my aunt next weekend.
to Study She will (she'll) study for the
exam after school.

The sentences don't have to be difficult, the main thing is
for the students to try making up their own sentences. They can use
some of the verbs and vocabulary in the textbook or else look them
up in a dictionary.

Too often teachers feel the more complicated the homework
assignment the better.
Since English is an "uncomplicated" language as far as grammar
is concerned, they should try teaching it in an "uncomplicated" way.

The main goal of teaching English is to get the students on the
road to conversing in the language. This means we want them to
learn by steps. First the basic grammar tenses, then going on to
immediately trying to use them! Once they are "talking" you'll
find that they are gaining confidence in themselves and this is the
motivation they need if they are to enjoy learning this language.